1. Field
The present invention relates to voltage converters and, more particularly, to DC-to-DC voltage converters.
2. Background
DC-to-DC converters are well-known in the art. Such circuitry or devices are typically employed to convert from one DC voltage signal level to another DC voltage signal level. This may be useful in a variety of embodiments.
One situation that is frequently an issue with such converters occurs when a sizable load is applied to the converter. A relatively sudden increase in load may be approximated as a step function and, as is well-known, typically results in a transient voltage signal in the circuitry to which the step function is applied. Therefore, typically a transient voltage signal will occur in those situations in which a sudden increase in load is applied to a DC-to-DC converter. Such transients, however, are undesirable because one of the functions of a DC-to-DC converter is to maintain an output voltage signal level within a particular voltage signal window or within a set of voltage signal boundaries to ensure, for example, that the operation of the circuitry being powered by the DC-to-DC converter is not substantially affected by the sudden increase in load.
One way that state of the art DC-to-DC converters address the situation is by employing bulk capacitance. Therefore, when the transient results from the application of a sizable load, the capacitors release stored charge to compensate at least partially for the transient voltage signal and to provide the DC-to-DC converter additional time to adjust to the increase in load.
Unfortunately, the use of bulk capacitance has several-disadvantages. For example, such capacitance takes up additional room in the system in which the DC-to-DC converter is being employed. Likewise, in production, adding this bulk capacitance to the circuitry is relatively inconvenient and, therefore, also introduces additional expense and time in the production process. Another approach is to employ what is referred to as ripple regulation. Where this approach is employed, the voltage and current may oscillate between different levels at a particular frequency. However, in some situations, these may undesirably affect overall performance and/or circuit operation because it may make it difficult to maintain tight tolerance on the output voltage and/or current, due at least in part to the amount of variation in voltage and current that may occur as a result of the ripple. Therefore, it would be desirable if a technique or method were available to maintain the output voltage signal level within the desired voltage signal window or voltage signal level bounds even when a sizable or significant load is applied, while reducing at least some of the disadvantages associated with the use of either standard ripple regulation and/or bulk capacitance.
Briefly, in accordance with one embodiment of the invention, a circuit includes: a DC-to-DC converter. The DC-to-DC converter includes a plurality of ripple regulator DC-to-DC converter circuits. The plurality of circuits are coupled so that the output signals produced by each of the ripple regulator DC-to-DC converter circuits is out of phase with respect to the other of the ripple regulator DC-to-DC converter circuits.